The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 10, 2004
Filed:
Jun. 19, 2000
Jaehyeong Kim, Pine Brook, NJ (US);
Steven F Swanchara, Randolph, NJ (US);
Lucent Technologies Inc., Murray Hill, NJ (US);
Abstract
A tracking circuit fine tunes the sampling time to a resolution of ⅛ Tc, where Tc is a chip duration after the searcher circuit finds the timing to within 0.5 Tc. Depending on the prior art tracking circuit that is being used, the input signals are early and late sampled PN despread pilot symbols or early, late and ontime sampled PN despread pilot symbols. Early and late samples are plus or minus one tick or Tt (one tick is ⅛ Tc) away from the ontime samples. The basic principle is that if early and late samples have about the same energy, then the timing is correct. If not, then the sampling time is changed to obtain a balance. In this invention, improved performance of the prior art tracking circuit is obtained by using pilot estimation results, not ontime pilot symbols. In one embodiment, pilot estimation results are low pass filtered signals of ontime symbols which are normally generated upstream of the tracking circuit.